Later this season, the Baltimore Symphony Orchestra will dive into pop material. Ray LaMontagne visits in a couple of weeks and the ABBA Orchestra puts its spin on "Dancing Queen" around Thanksgiving. However, the BSO is kicking things off with more folk-infused programs. Last week, bluegrass outfit Time for Three took the Strathmore stage. On Thursday evening, traditional sounds from Eastern Europe will fill the Music Center.

"I started thinking about how much of classical music is influenced by folk elements," says music director Marin Alsop. "I wanted to make that connection back to its world music roots."

Before the BSO takes on Bartók's "Concerto for Orchestra" and Tchaikovsky's "Violin Concerto," Cleveland-based Harmonia will introduce the audience to melodies from Hungary, Romania, Russia, Croatia and the Ukraine.

"I grew up surrounded by Eastern European music," says founder and accordionist Walt Mahovlich. "There are lots of immigrants from Eastern Europe here, so I heard this stuff from the time I was a kid."

The 58-year-old started playing with other musicians in the late 1980s, but Harmonia's current incarnation began in 1999. The group has grown to six full-time members with instruments ranging from accordion to violin and cimbalom hammered dulcimer.

"We've played on a lot of big stages, but we're still very active in our communities," Mahovlich says. "So it's not unusual for us to play at a Hungarian or Slovak wedding because that's really part of us."

Only Mahovlich and violinist Steven Greenman were born in the U.S. The rest of the ensemble consists of trained musicians from the region. Mahovlich notes that the fall of communism provided a boom in talent.

"When the Berlin Wall came down, suddenly musicians of a caliber that we hadn't seen in a while were able to come here," he explains. "They were stuck in the Eastern Bloc. If they moved here, that meant cutting off contact with their friends and family."

A polymer scientist by trade, Mahovlich is excited that his group is taking off. Harmonia has played all over the country, including the Kennedy Center. Every member has performed with an orchestra, but this is the first time they will show off their Gypsy-inspired tunes in front of a classical audience together. They should mesh well considering Bartók was influenced by folk.

"I think it's going to be a great to hear our music juxtaposed with the music of Bartók," Mahovlich says. "We know that Bartók was shaped, and always given a type of freedom, by his exposure to the traditional folk music. He drew from a lot of sources."

The BSO will close the evening with Tchaikovsky's "Violin Concerto," with James Ehnes in the spotlight. The 33-year-old violinist has been playing with full orchestras for 20 years. He made his debut with the Montreal Symphony Orchestra at 13, and first worked with Alsop a year later when she was director of the Long Island Philharmonic.

"He's just grown tremendously as an artist," Alsop says. "He can play all styles of repertoire equally well. I just think he's a consummate soloist and violinist, and a lovely person, too."

Despite success at such an early age, Ehnes maintained a level head. Maybe that's because classical music wasn't the rage in his native Brandon, Manitoba.

"I grew up in the kind of town where being a talented young classical musician came with as much ridicule from your peers as respect," he says. "So I learned never to take my success too seriously. The real stars in my town were the hockey players."

"Violin Concerto" is more than familiar to Ehnes. The Juilliard alum estimates he has performed the piece close to 50 times, but still finds joy in playing it.

"I love it every time," he says. "It has everything that one could want in a violin concerto — beautiful melodies, virtuosity, some very interesting and unique technical innovations and a great orchestral part as well."

Ehnes may parade his talent all over the world — he answers questions via e-mail from Japan — but he has found a home with his ballet dancer wife Kate in Bradenton, Fla.

"She moved down in 2000, and I followed her down there in 2001," he explains. "We both fell in love with the area and decided to stay. I spend so much time on the road in big cities, so it is nice for me to come home to a quiet little town."

This is Alsop's third season as music director of the BSO. The New York City native made history in 2007 when she became the first female head of a major orchestra. The novelty wore off quickly.

"It got old even after the first time they said it," she confesses. "The correct way to look at is there are no other women leading major American orchestras, but I'm hoping that will change in the next five to 10 years."

This season has already proven difficult for orchestras around the world. Many have either shortened their schedules or chosen works that require fewer musicians. The BSO, however, will continue to hold court in Baltimore as well as North Bethesda.

"I think it's always difficult when you have to look over your shoulder and make sure everything you do is as economical as possible," Alsop says. "But I think at the BSO, we've managed to find a balance between being fiscally responsible and maximizing every opportunity to be creative.

"I don't think you need a lot of money to be creative; you just need to have a lot of ideas."

The Baltimore Symphony Orchestra performs with Harmonia and James Ehnes at 8 p.m. Thursday in the Music Center at Strathmore, 5301 Tuckerman Lane, North Bethesda. Tickets range from $28 to $90. Call 877-BSO-1444 or visit www.BSOmusic.org.